In such cheese-producing textile machines, for example automatic cheese-winding machines, it has been customary for some time that the textile machines differ in respect to the special demands of the various textile companies both as to their output as well as their equipment. The same applies to the associated service units which also can be provided in different equipment variations.
For example, the automatic cheese-winding machine can be equipped with an additional cheese storage means. Such a design of the textile machine results in a bobbin deposition which differs from the "normal" bobbin deposition position, and such must be taken into consideration by the associated service unit through appropriate adaptation of the control of the related handling elements.
The service units can also differ by provision of additional features. For example, the service unit can be operated with or without a blower device, or can have a complementary mechanical device which makes it possible to provide the completed cheeses with an additional reserve top winding.
When operating a service unit with a blower device, the rotational speed of the drive motor of the service unit must be adapted to the blower device, along with a changed drive gear. The provision of a mechanical top reserve winding device requires a change in the functional sequence of the service unit.
Heretofore, it has been customary to adapt the control of these service units by means of a corresponding structural hardware control configuration, e.g., the adaptation of the control to the respective structural configuration of the service unit or the textile machine is accomplished by the insertion of wire bridges into the wiring of the control unit.
However, it is also known in the structural configuration of such service units to employ additional switching elements, socalled pre-selection switches. In this case the pre-selection switches have a plurality of manually operable switches which must be individually set in correspondence to the respective structural configuration of the service units, which requires a relatively large amount of time. Furthermore, such pre-selection switches are quite expensive.
An automatic cheese winding-machine is known from German Patent Publication DE 42 21 504 A1, whose work stations are connected with a service vehicle via a bus line. If one of the work stations requires service, the work station transmits an optical signal, which is detected by the service unit patrolling in front of the work stations. After the service unit has been positioned at the respective work station, the service unit acknowledges the signal by a light signal to the work station. The respective work station is activated by this light signal to subsequently enable the service vehicle to issue work commands via the bus line to the respective work station.
Another textile machine arrangement is described in European Patent Publication EP 0 536 540 B1, which enables the exchange of data between several service units and a central station. In this case, the service units are conducted along a closed track system extending along the work stations of the textile machines. The track system has current conductors as well as separate data lines, to which the service units are respectively connected by a wiper contact device. The track-bound conductor system has at least two and at most three data lines, which are respectively connected to form a ring line, to which the transmitter/receiver devices of the central station and the transmitter/receiver devices of the service units are connected. The data are transmitted by the transmitter devices in the form of pulses of a predetermined pulse length and with predetermined spacing, wherein each data pulse is simultaneously transmitted with opposite polarity to two data lines. The receiver devices are designed such that only those incoming pulses which are received simultaneously via both data lines and have a predetermined minimum signal output are evaluated.
A further variant of a data transmission means between a service unit of a textile machine and a central control unit of the textile machine is known from German Patent Publication DE 42 12 629 A1. With this device, the communication between the service unit and the machine control computer of a ring spinning machine takes place via current lines which are already present. One respective interface is placed between the computer of the service unit and the current conductor as well as between the machine control computer of the ring spinning machine and the current conductor, which makes it possible to utilize the lines, which actually are intended for current supply, also for data transmission.